Installing Magento 1.9.1 on Bitnami Nginx Stack

First download the Bitnami Nginx Stack Magento.
Install the Bitnami Stack where you like, called by me root_nginx_stack.

After installation copy the demo project to the apps folder and remove htdocs folder

1. cd root_nginx_stack
   cp -r docs/demo/ apps/magento
   rm -rf apps/magento/htdocs
   unzip magento-1.9.1.0.zip
   mv magento root_nginx_stack/magento/apps/htdocs
   
2. change in root_nginx_stack/magento/*.conf all reference 'demo' to 'magento'
3. in root_nginx_stack/nginx/conf/bitnami/bitnami-apps-prefix.conf add the line
   include "root_nginx_stack/apps/magento/conf/nginx-prefix.conf";
4. in root_nginx_stack/magento/nginx-vhosts.conf add the lines below before the include directive

   
       location / {
           index index.html index.php; ## Allow a static html file to be shown first
           try_files $uri $uri/ @handler; ## If missing pass the URI to Magento's front handler
           expires 30d; ## Assume all files are cachable
       }
       
       location @handler { ## Magento uses a common front handler
           rewrite / /index.php;
       }
   

5. in root_nginx_stack/magento/nginx-app.conf replace the location part with the lines below and set your root_nginx_stack path.

   location ~ \.php$ {
       if (!-e $request_filename) { rewrite / /index.php last; } ## Catch 404s that try_files miss
   
       expires        off; ## Do not cache dynamic content
       fastcgi_split_path_info ^(.+\.php)(/.+)$;
       fastcgi_read_timeout 300;
       fastcgi_pass unix:/root_nginx_stack/php/var/run/www.sock;
       fastcgi_index index.php;
       fastcgi_param  SCRIPT_FILENAME $request_filename;
       include fastcgi_params;
   }
   
       ## These locations would be hidden by .htaccess normally
       location ^~ /magento/app/                { deny all; }
       location ^~ /magento/includes/           { deny all; }
       location ^~ /magento/lib/                { deny all; }
       location ^~ /magento/media/downloadable/ { deny all; }
       location ^~ /magento/pkginfo/            { deny all; }
       location ^~ /magento/report/config.xml   { deny all; }
       location ^~ /magento/var/                { deny all; }
   
       location /magento/var/export/ { ## Allow admins only to view export folder
           auth_basic           "Restricted"; ## Message shown in login window
           auth_basic_user_file htpasswd; ## See /etc/nginx/htpassword
           autoindex            on;
       }
   
       location  /magento. { ## Disable .htaccess and other hidden files
           return 404;
       }
   
   
       location ~ .php/ { ## Forward paths like /js/index.php/x.js to relevant handler
           rewrite ^(.*.php)/ $1 last;
       }
   

6. create a database for your magento installation:

   /root_nginx_stack/mysql/bin/mysql -uroot -p
   ...
   create database bitnami_magento;
   grant all privileges on bitnami_magento.* to 'bn_magento'@'localhost' identified by 'MAGENTO_PASSWORD';
   

7. restart nginx and type in your browser: http://localhost:8080/magento/index.php
   your magento installation starts now!

I got the references for this config from Bitnami Wiki and Magento Wiki.
It's not production ready but helps as a starting point.

How to delete orders

Usually you have after a certain time of developing some test orders that you want go get rid of. this is a small script to delete them

// if you run this code in a shell, see comment below, you have to set this flag
Mage::register('isSecureArea', true);

// select all orders
$orders = Mage::getModel('sales/order')->getCollection();

// select defined orders listed in $orderIds  
$orders = Mage::getModel('sales/order')->getCollection()
    ->addFieldToFilter('entity_id', (array) $orderIds);

foreach ($orders as $order) { 
    $order->delete(); 
}

you can run code snippet like above with a php shell as provided in Magento PHP Developer's Guide (p.58)

Bulk update products to be in/out of stock programatically

This is an example to set all (filtered) products to be in stock with quantity of 1.

$products = Mage::getModel('catalog/product')->getCollection();
// filter your product list
$products = $products->addFieldToFilter($attribute_code, $attribute_value)->load();

foreach($products as $product){
 $stockItem = Mage::getModel('cataloginventory/stock_item')->loadByProduct($product); 
 $stockItem->setData('is_in_stock', 1);
 $stockItem->setData('qty',1);
 $stockItem->save();
}

Converting wav files to flac with python and audiotools

This is not about Magento programming ;-)

I was looking for a (free) tools to convert all my wav files to flac. As such, not a special task, there are many tools around. But all the GUI tools I found, had big issues to run in batch mode with thousands of files to convert. 

Eventually I found track2track from audiotools. The only problem was here, I couldn't get it working in batch mode with setting the right params for the output (converted) file names. So I decided to wrap my own script around audiotools. 

Certainly not really performant, but it does the job.
Here my first try:

from Queue import Queue
import logging
import os
from threading import Thread
import audiotools
from audiotools.wav import InvalidWave

"""
Wave 2 Flac converter script
using audiotools
"""
class W2F:

    logger = ''

    def __init__(self):
        global logger
        # create logger
        logger = logging.getLogger(__name__)
        logger.setLevel(logging.DEBUG)

        # create a file handler
        handler = logging.FileHandler('converter.log')
        handler.setLevel(logging.INFO)

        # create a logging format
        formatter = logging.Formatter('%(asctime)s - %(name)s - %(levelname)s - %(message)s')
        handler.setFormatter(formatter)

        # add the handlers to the logger
        logger.addHandler(handler)

    def convert(self):
        global logger
        file_queue = Queue()
        num_converter_threads = 5

        # collect files to be converted
        for root, dirs, files in os.walk("/Volumes/music"):

            for file in files:
                if file.endswith(".wav"):
                    file_wav = os.path.join(root, file)
                    file_flac = file_wav.replace(".wav", ".flac")

                    if (os.path.exists(file_flac)):
                        logger.debug(''.join(["File ",file_flac, " already exists."]))
                    else:
                        file_queue.put(file_wav)

        logger.info("Start converting:  %s files", str(file_queue.qsize()))

        # Set up some threads to convert files
        for i in range(num_converter_threads):
            worker = Thread(target=self.process, args=(file_queue,))
            worker.setDaemon(True)
            worker.start()

        file_queue.join()

    def process(self, q):
        """This is the worker thread function.
        It processes files in the queue one after
        another.  These daemon threads go into an
        infinite loop, and only exit when
        the main thread ends.
        """
        while True:
            global logger
            compression_quality = '0' #min compression
            file_wav = q.get()
            file_flac = file_wav.replace(".wav", ".flac")

            try:
                audiotools.open(file_wav).convert(file_flac,audiotools.FlacAudio, compression_quality)
                logger.info(''.join(["Converted ", file_wav, " to: ", file_flac]))
                q.task_done()
            except InvalidWave:
                logger.error(''.join(["Failed to open file ", file_wav, " to: ", file_flac," failed."]), exc_info=True)
            except Exception, e:
                logger.error('ExFailed to open file', exc_info=True)

As you can see, there is a bit of multithreading implemented. Looks like it works a bit faster than my first try. Anyway, it's only a dummy example, improve it as you like!

How to get Magento's attribute names and values

For my own reference, quick and dirty:

$product = Mage::getModel('catalog/product')->load($productId);
$attribute_value = $product->getData($attribute_code);

The attribute code used below is 'attribute_code'.

/**
 * get attribute collection
 */
$attribute = $_product->getResource()->getAttribute('attribute_code');

/**
 * get attribute type
 */
$attribute->getAttributeType();

/**
 * get attribute label
 */
$attribute->getFrontendLabel();

/**
 * get attribute default value
 */
$attribute->getDefaultValue();

/**
 * check if the attribute is visible
 */
$attribute->getIsVisible();

/**
 * check if the attribute is required
 */
$attribute->getIsRequired();

/**
 * get attribute value
 */
$attributeValue = Mage::getModel('catalog/product')->load($_product->getId())->getAttributeCode();

//or without loading the product
$attributeValue = Mage::getResourceModel('catalog/product')->getAttributeRawValue($productId, 'attribute_code', $storeId);

/**
* get attribute option code/value list 
*/
$attribute = Mage::getSingleton('eav/config')->getAttribute('catalog_product', 'attribute_code');
$options = $attribute->getSource()->getAllOptions(false);

in a view.php or similar, you can access the attribute text related to a product like:

<?php echo $_product->getAttributeText('attribute_code'); ?>